<!DOCTYPE html>
<html lang="en">
<head>
    <meta charset="UTF-8">
    <meta http-equiv="X-UA-Compatible" content="IE=edge">
    <meta name="viewport" content="width=device-width, initial-scale=1.0">
    <title>Document</title>
</head>
<script type="module"> 
//原本script脚本放在上面是不行的，因为下面的button代码还没有解析，访问不到
//但是加上模块之后，自动为严格模式"use strict"
     console.log(document.querySelectorAll("button"));
 
</script>
<body>
     <button>唐玮</button>
</body>
</html>